The present invention relates to sign board lighting control systems, and more particularly to a system whereby programming and reference instructions are conveyed to remote, individual sign board lighting control units by means of radio transmissions such that the lighting systems associated with such units operate in accordance with predetermined lighting protocols or modes.
Sign board lighting systems have come into wide use for illuminating outdoor billboards and the like during the time period between sunset and sunrise. Sign boards which require such illumination exist in very diverse locations, such as along highways or on buildings, and often in very remote places. Moreover, sign boards owned and maintained by a major outdoor advertising company can be located hundreds, or even thousands, of miles apart.
Because it is neither necessary nor desirable to continuously illuminate sign boards, sign board lighting systems are operated only during certain, discreet time periods, or lighting protocols. Typically, such lighting protocols are established by contract between an advertiser and the sign board owner, and may, for example, be from sunset to sunrise or from sunset, until a certain specified time at night. By accurately conforming the time period during which the sign board lighting system is activated to the protocol required by the contract, significant savings are realized from decreased electrical power consumption and extended lamp life.
Prior systems for controlling sign board lighting typically utilized photocells, timers or a combination thereof, to regulate the lighting circuitry. Because of inherent deficiencies in these designs, the operation of such sign board lighting control systems was often less than optimum.
For example, since the time of sunset at a particular sign board location varies on a daily basis and therefore cannot be readily established with a conventional timer, photocells were often utilized to activate a sign board lighting system at sunset. However, such photocells proved to be a crude means of determining the time of sunset, because variations in atmospheric conditions caused the light intensity measured by the photocells at the time of actual sunset to fluctuate dramatically. Thus, on cloudy days such systems would sometimes illuminate the sign board long before sunset. This was an even greater problem in areas where the photocell lens became dirty or otherwise obstructed with time.
Often it is required to alter the lighting protocol of a particular signboard, i.e., to change the times each day when the lighting system is to be activated or deactivated. For example, it is common for a contract between advertiser and sign board owner to require that the sign board lighting system be deactivated at a particular local time each day. In such a case, upon a time change from "standard time" to "daylight savings time," or vice-versa, the mode of operation of the sign board lighting system must be altered to account for the hour time change. Or, for example, the advertiser contracting for the sign board may decide that the sign should remain illuminated to a later time, say midnight instead of 10:00 p.m. Or, upon the expiration of the advertising contract, the owner of the sign board may wish to completely discontinue illuminating the sign board until a new advertiser is secured.
In order to alter the lighting protocol of prior sign board illumination systems it was necessary for a repair crew to visit the sign board site. Because of the diverse, remote and often virtually inaccessible location of many sign boards, this was often an arduous, time-consuming and expensive task.
Certain prior sign board lighting control systems utilized radio transmissions to actuate the systems. The sign boards were categorized into groups of one or more sign boards and turned on or off as a group in response to radio signals. Where a large number of geographically separated sign boards exist, such systems are not practical because of the high cost and time required to send individual radio signals to each sign board or group of sign boards. Moreover, as with sign boards controlled by photocells and timers, such prior sign board lighting control systems did not provide the capability to remotely program the lighting protocol of individual sign boards.
It has been proposed that a control system be developed whereby individual sign boards may be controlled by radio signals. However, such a system would prove unduly expensive because major sign board companies own thousands of sign boards. Since each sign board would require its own transmissions, an excessive number of transmissions would be necessary to effectively control the system.
The present invention overcomes these drawbacks by providing a system whereby both programming and timing signals are communicated to a sign board lighting control system. In particular, the invention provides for transmissions of coded programming signals which designate a particular lighting protocol to a particular sign board. Additionally, the invention provides for timing signals necessary for performing the various different lighting protocols of multiple sign board lighting control units to be accomplished by a limited number of universal reference transmissions received by all sign boards.
A control unit associated with an individual sign board lighting system includes a receiver capable of intercepting the radio-transmitted coded programming and timing signals and control circuitry capable of decoding such signals and either storing in memory programming signals or executing functions in response to timing reference signals, as the case may be.
Accordingly, it is a general object of the present invention to provide a new and improved control system for sign board lighting systems or the like.
It is a more specific object of the present invention to provide a new and improved control system for sign board lighting systems wherein the system comprises a computer controlled radio frequency transmitter for transmitting coded programming and timing reference signals to a radio frequency receiver associated with individual sign boards, which signals are utilized by a control unit which actuates or deactivates the sign board lighting system in response to the coded signals. This remote programming capability eliminates the need for "on-site" programming.
It is an additional object of the present invention to provide a new and improved sign board lighting control system whereby commercially available "paging" or "beeper" systems transmit coded programming or timing reference signals to control units associated with individual sign board lighting systems. The control units decode the signals and activate or deactivate the sign board lighting system in accordance with the programming and timing reference signals.